Feeding mechanism of sewing machines



1961 LA. LESLIE 2,996,024

FEEDING MECHANISM OF SEWING MACHINES Filed Jan. 19, 1959 Inventor =4 van ,lexsnder lax/ United States PatentO 2,996,024 FEEDING MECHANISM OF SEWING MACHINES Ivan Alexander Leslie, Fairwater Parkfield Drive, Nantwich, England Filed Jan. 19, 1959, Ser. No. 787,540 Claims priority, application Great Britain Feb. 3, 1958 Claims. (Cl. 112-210) This invention relates to the mechanism for feeding the Work past the needle in sewing machines, and the object of the present invention is to provide a simple form of work feed mechanism which permits of the size of the stitch and, if desired, the direction of feed of the work being readily varied, as may be required.

According to the invention, the work feed mechanism of a sewing machine comprises a work feed member capable of vertical and horizontal or lateral movement, a cam member on a hollow driving shaft for imparting a vertical movement to the feed member, a lever housed within said shaft and having an end thereof projecting from an end of the shaft, means for adjusting the angular position of the lever in relation to the shaft to vary the eccentricity of said projecting end of the lever in relation to the axis of the shaft, and means for transmitting the throw of the said end of the lever to the work feed member end of the lever for imparting a horizontal or lateral movement to be imparted thereto.

The work feed member may carry a depending slotted part engaged by the projecting end of the lever.

Conveniently the lever has inclined or cam surfaces engaged by contacting parts on a sliding collar movable along the shaft to vary the degree of eccentricity of the projecting end of the lever. The inclined or cam surfaces on the lever may be such that by the action of the sliding collar the end of the lever may be caused to assume an initial feed-starting position either above or below the axis of the shaft, according to the desired direction of feed of the work.

FIGURE 1 of the accompanying drawing is a vertical section through the work feed mechanism of a sewing machine in accordance with the present invention.

FIGURE 2 is an end elevation of the mechanism as viewed from the left-hand end of FIGURE 1.

FIGURES 3, 4, 5, 6 and 7 represent diagrammatically a number of modifications of the arrangement shown in FIGURES 1 and 2.

Referring to FIGURES 1 and 2 of the drawing, the feed mechanism shown therein comprises a fixed frame 1 to the top of which is pivoted, at 2, a horizontally swingable work feed member consisting of a flexible spring steel strip 3 capable of flexing in a vertical position, as shown by dotted lines, and having at the end remote from the pivot 2, a turned-up work-gripping part 4 projecting through a slot 5 in a top work-supporting plate 6 and having a toothed upper edge 7 (FIGURE 2) which, when sewing is in operation, lies beneath the material and co-operates with the presser foot 9 to feed the work material past the needle 10 of the machine.

The said feed member 3 is provided on its underside, towards its free end, with a depending bracket 11 having a top flange 12 and its lower portion being bifurcated to provide an open vertical slot 13. Vertical movement is given to the feed member 3, to cause it to grip the work material, by means of a cam 14 engaging beneath the flange 12 of bracket 11 and being carried by the end of a hollow driven shaft 15 mounted to turn in the frame 1.

In order to impart to the feed member 3 a horizontal feed motion simultaneously with the vertical motion, the slot 13 in the bracket 11 is engaged by a cylindrical pinlike end 16 of a lever 17 housed within the hollow shaft 15 and pivoted therein at 18 which position is vertically below the position 2 on the top of the frame 1 at which 2,996,024 Patented Aug. 15, 1961 the spring steel strip 3 is pivoted. The lever 17 is of a length such that the end 16 projects from the open end of the shaft sufliciently to engage the slot 13, and an intermediate portion of the lever is provided, on opposite sides, with inclined cam surfaces 19, 19, engaged by contact pegs 20, 20, at opposite sides of a collar 21 slidably mounted on the exterior of the shaft 15, the pegs 20 sliding in slots 22 in the shaft. The collar 21 has an annular groove 23 engaged by a fork 24 on a slidable control rod 25 mounted in the frame 1 and provided at its rear end with a knob for manual operation.

By sliding the collar 21 along the shaft the amount of eccentricity of the end 16 of lever 17, in relation to the axis of the shaft 15, can be varied; and the form of the cam surfaces 19 may be such that in the initial feed position of the feed member 3, the pin-like end 16 of lever 17 may take an eccentric position in the slot 13 either above or below the axis of the shaft 15. It will be clear that as the shaft 15 rotates together with the lever 17, the cam 14 will cause the feed member 3 to lift to engage the work, and simultaneously the eccentric pin end 16 of the lever, by moving in a circular path, will cause the said feed member to move horizontally from an initial position in order to feed the work material beneath the needle.

By sliding the collar 21 along the shaft in one direction or the other the amount of eccentricity of the pin end 16 will be varied, and thus the size of the stitch may be adjusted as required. Further, by moving the collar to a position such the pin end 16 is above or below the axis of the shaft in the initial feed position, so will the feed motion be in one direction or the other.

If desired, the feed member 3 may be pivoted to the underside of the top plate 6 instead of to the frame 1.

FIGURE 3 shows a modification in which the lever 17 having pin end 16, is pivoted at 18 between its ends, forming two arms of which the rear arm 26 has inclined top and bottom cam surfaces engaged by the pegs 20 of sliding collar 21.

FIGURE 4'illustrates a modification in which the work feed members consists of a vertical lever 27 adapted to have a lateral angular movement imparted to it by the pin end 16 of the lever 17 (in FIGURE 1) engaging a vertical slot 28, the lower end of the said lever 27 having a slot 29 engaged by a fixed pivot pin 39 which arrangement enables a vertical movement to be imparted to the feed member by cam 14 engaging a shoulder 31, as in FIGURE 1.

In another arrangement (FIGURE 5) the feed member consists of a vertical plate 32 slidable in guide parts 33 having shanks 34 slidably gm'ded horizontally, said plate having a slot 35 engaged by the pin end 16 of the rotating lever (17 in FIGURE 1) to impart a lateral horizontal movement to the feed member, and a vertical movement being given by cam 14 as before.

According to FIGURE 6, the feed member consists of a lever 36 having a toothed upper edge and pivoted to a vertical link 37 jointed at its lower end to a fixed part. This arrangement permits of a vertical movement being given by cam 14 as before, simultaneously with a horizontal movement by the lever end 16 engaging the vertical slot 13 The arrangement shown in FIGURE 7 permits of the feed member being rendered inoperative when the machine is being used for darning. The said feed member consists of a lever 38 resting on elevating cam 14 and provided with a slotted bracket 39 engaged by the pin end 16, as before, said lever being pivoted at 40 to the upper end of a vertical link 41 pivoted at its lower end, at 42 upon a crank or eccentric 43. As an alternative to the slotted bracket 39, the pin end 16 may be coupled by a link 44 to the vertical link 41, as shown by broken lines.

The pivot 42 can be lowered by the crank or eccentric so that the feed member operates normally, but the said pivot 42 can be raised by turning the eccentric, thereby tilting the feed member about the cam 14 and rendering it inoperative.

The terms vertical and horizontal used in the description and claims are intended to include cases where the movement or position of the parts is nearly vertical or nearly horizontal.

I claim:

1'. In a work feed mechanism of a sewing machine: a work feed member movable in vertical and lateral directions, a rotatable hollow driving shaft provided with longitudinal slots and extending in the longitudinal direction of said work feed member, and having an open end, a cam mounted on said shaft and engaging said work feed member adjacent the work-engaging end thereof for imparting a vertical movement to said work feed member, a lever housed within said hollow shaft and pivoted directly and transversely to said shaft so as to be rotatably connected thereto, said lever having longitudinal cam surfaces thereon and an extension projecting from said open end of said shaft, a slidable collar movably mounted on said shaft and having contact parts projecting through said slots in said shaft and engaging said cam surfaces for varying the degree of eccentricity of the projecting extension of said lever by sliding the collar along said shaft, and a depending part arranged on said work feed member and having a vertical slot engaged by the projecting extension of said lever and operable by the latter for imparting a lateral movement to said work feed member.

2. A work feed mechanism of a sewing machine according to claim 1 which includes means for moving said collar into any one of a plurality of initial feed starting positions selectively above or below the axis of said shaft in conformity with the desired direction of feed of the work.

3. A work feed mechanism according to claim 1, in which the work feed member comprises a resilient flexible member having one end portion for engagement with the work to be fed, and a stationary part having the other end of said flexible member pivotally connected thereto for lateral swinging movement of said flexible member.

4. In a work feed mechanism of a sewing machine: a

work feed member movable in vertical and lateral direc- 4 tion and comprising a resilient flexible member disposed substantially horizontally, one end of said resilient flexible member being arranged for engagement with the work to be fed, a stationary part having pivotally connected thereto the other end of said resilient flexible member for lateral swinging movement thereon, a rotatable hollow driving shaft provided with longitudinal slots and extending in the longitudinal direction of said work feed member, said shaft having an open end adjacent the workengaging end of said resilient flexible member, a cam connected to said shaft and engaging the work feed member adjacent the work-engaging end thereof for imparting vertical movement thereto, a lever housed within said hollow shaft and pivoted directly and transversely to said shaft so as to be rotatably connected therewith, said lever having an end projecting from said open end of said shaft and having longitudinal cam surfaces, said lever being angularly adjustable in relation to said shaft for selectively varying the eccentricity of said projecting end of said lever in relation to the axis of said shaft, a slidable collar slidably mounted on said shaft and having contact points extending through said slots and engaging said cam surfaces for varying the degree of eccentricity of said projecting end of said lever by sliding the collar to different positions along the shaft, said feed member having a depending portion with a vertical slot engaged by the projecting end of said lever for giving a lateral movement to said work feed member.

5. A work feed mechanism according to claim 4, in which said lever is pivoted to said hollow shaft at a position substantially vertically below the position on the stationary part at which the resilient flexible member is pivoted.

References Cited in the file of this patent UNITED STATES PATENTS 811,426 Mitchell Ian. 30, 1906 1,119,272 Gould Dec. 1, 1914 1,321,086 Centervall Nov. 11, 1919 1,387,145 Flanagan Aug. 9, 1921 1,818,304 Chevalier Aug. 11, 1931 2,725,023 Ayres Nov. 29, 1955 FOREIGN PATENTS 242,851 Germany Jan. 22, 1912 945,060 Germany June 28, 1956 

